Risk Assessment of Side Branch Compromise After Coronary Bifurcation Stenting　- A Substudy of the 3D-OCT Bifurcation Registry.

BACKGROUND: Side branch (SB) occlusion during bifurcation stenting is a serious complication. This study aimed to predict SB compromise (SBC) using optical coherence tomography (OCT).Methods and Results: Among the 168 patients who enrolled in the 3D-OCT Bifurcation Registry, 111 bifurcation lesions were analyzed to develop an OCT risk score for predicting SBC. SBC was defined as worsening of angiographic SB ostial stenosis (≥90%) immediately after stenting. On the basis of OCT before stenting, geometric parameters (SB diameter [SBd], length from proximal branching point to carina tip [BP-CT length], and distance of the polygon of confluence [dPOC]) and 3-dimensional bifurcation types (parallel or perpendicular) were evaluated. SBC occurred in 36 (32%) lesions. The parallel-type bifurcation was significantly more frequent in lesions with SBC. The receiver operating characteristic curve indicated SBd ≤1.77 mm (area under the curve [AUC]=0.73, sensitivity 64%, specificity 75%), BP-CT length ≤1.8 mm (AUC=0.83, sensitivity 86%, specificity 68%), and dPOC ≤3.96 mm (AUC=0.68, sensitivity 63%, specificity 69%) as the best cut-off values for predicting SBC. To create the OCT risk score, we assigned 1 point to each of these factors. As the score increased, the frequency of SBC increased significantly (Score 0, 0%; Score 1, 8.7%; Score 2, 28%; Score 3, 58%; Score 4, 85%; P<0.0001). CONCLUSIONS: Prediction of SBC using OCT is feasible with high probability.

Treatment strategy modification and its implication on the medical cost of fractional flow reserve-guided percutaneous coronary intervention in Japan.

BACKGROUND: Fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) could improve outcome compared with angiography-guided PCI. However, the economic impact of FFR-guided PCI remains largely unknown in the medical system in Japan. We evaluated the impact of treatment strategy modification by FFR measurement on the direct medical cost using a model analysis with a decision tree model in Japan. METHODS: For the clinical parameters set in the model, the findings from CVIT-DEFER registry were adopted. Cost parameters were considered on the assumption that coronary angiography, FFR measurement, and the treatment are performed at Diagnosis Procedure combination (DPC) hospitals, and the costs were calculated based on the medical fee reimbursement systems in Japan. RESULTS: The probability of deferral of PCI in patients who were allocated to PCI based on coronary angiography was set as 90.1% based on the CVIT-DEFER registry. In the model analysis, the cost of tests was increased by 185,660 JPY per patient by the addition of FFR measurement, but the cost of treatment with PCI was reduced by 561,425 JPY per patient, and the entire cost of treatment was reduced by 322,675 JPY, resulting in the expected reduction in the total expected medical cost by 137,015 JPY per patient. CONCLUSION: Under contemporary Japanese practice, FFR-guided PCI has potential to reduce the medical cost by effective reassessment of coronary stenosis and reducing inappropriate application of PCI.